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Questions tagged [libalsa]

The ALSA (Advanced Linux Sound Architecture) library

The ALSA (Advanced Linux Sound Architecture) library

http://www.alsa-project.org/main/index.php/Main_Page

68 questions
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ALSA Configuration How To Combine MMAP Emulation and Ladspa Plugin in asound.conf

I have a working PCM output with good sounding audio on a Raspberry Pi compute module ( Linux ) using the rpi dac. The 'aplay -l' command output shows the following: >> aplay -l **** List of PLAYBACK Hardware Devices **** card 0: sndrpirpidac…
PhilBot
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ALSA application to read and play a WAV file on Raspberry Pi

Trying to learn the ALSA audio layers to eventually write an ALSA device driver for the Raspberry Pi platform. Starting simple, I glued together various samples from the ALSA project site and other online sources to do the simplest thing: read a WAV…
Mark McMillan
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ALSA lib pcm_hw.c:1667:(_snd_pcm_hw_open) Invalid value for card arecord: main:722: audio open error: No such file or directory

i am working on speech recognition . for this i am using "alsa-utils" but when i try to use this script #!/bin/bash echo “Recording… Press Ctrl+C to Stop.” arecord -D plughw:1,0 -q -f cd -t wav | ffmpeg -loglevel panic -y -i – -ar 16000…
Aaditya Ura
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Sharing a microphone audio stream on Linux

As much as it matters my scenario is developing an accessibility application not any kind of malicious eavesdropping, whereas also within this scenario there are various research and development implied scenarios, all of which should greatly benefit…
matanster
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2 answers

how to solve these ALSA errors

import speech_recognition as sr listener= sr.Recognizer() try: with sr.Microphone() as source: print("hai say something...") voice = listener.listen(source) command = listener.recognize_google(voice) …
SOORYADEV
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aplay piping to arecord using a file instead of stdin and stdout

Below command will record the data from default device and output it on stdout and aplay will play the data from stdin. arecord -D hw:0 | aplay -D hw:1 - Why we prefer stdin and stdout instead of writing into a file and reading from it as…
user3053970
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How to get PCM device path in ALSA?

What is the easiest way in ALSA library to get the file name of the physical playback device from a pcm handle or name? For example for the pcm device hw:0,0 I would like to get the /dev/snd/pcmC0D0p. This is rather simple (just transfer the…
Brain
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ALSA Lib 1.1.2 Compilation error

I am trying to cross compile ALSA Lib application for linux-arm based processor. I am using eclipse to do the build for me. The build phase of the application is successful but I get errrors when the gcc linker tries to complete. I get the following…
JavaProgrammer
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ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card

I'm currently trying to use the ALSA lib to emit sounds. However, I'm getting this following error: Setting random seed to 345. Adding stimulus TestBeep... ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card Process Process-1: Traceback…
unixcorn
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How to use alsa library API to work with Headphone and Speaker?

I want to implement (mute/unmute and volume up/down) for Speaker and Headphone using c program.Using amixer command line utility as shown in this link…
raj123
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pyAlsaaudio install on openSUSE

I'm trying to install pyAlsaaudio on my openSUSE distro Output of uname -a: Linux linux-0cd5 4.12.14-lp150.12.48-default #1 SMP Tue Feb 12 14:01:48 UTC 2019 (268f014) x86_64 x86_64 x86_64 GNU/Linux I downloaded the source from this…
rajan
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play multiple wav files simultaneously using alsa c api

I want to implement a specific functionality to my project which includes continuously playing a sample-default.wav in the background and play a sample-specific.wav file when some specific condition matches. What I really want is that, when…
iamNitin16
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Programmatic ALSA loopback

I need some pointers where to start with the following: From any application that plays audio using ALSA to the connected speaker I'd like to grab the samples and do some audio processing. I am not in control of the player and I'd like to be able to…
kwasmich
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ALSA Bad file descriptor and robot voice

I am working on a linux embedded device and each time I start to play an audio stream the call to snd_pcm_start, returns the -77: which means "File descriptor in bad state". #define EBADFD 77 /* File descriptor in bad state */ I rebuild the…
peregrinus
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How to list ALSA MIDI clients without reading `/proc/asound/seq/clients`?

Is there a known way to list existing MIDI clients using the ALSA API only, without reading the special file /proc/asound/seq/clients? I searched the ALSA MIDI API reference, and could not find any match. I believe there must be a way to achieve…
Hibou57
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